Resonant electrical relay



July 7,1M931. c. B. MlRlcK 1,813,899

RESONANT ELE OTRI CAL RELAY Filed Sept. l, 1925 2e mgl! l mmm il 23 20 E 19 avfffzllimlm; a 22 'Wow l V V l 1f N I@ Z0 /7 i; 1 I7 I E r\4- l .fil l le. w y 1 u v i .5

gwuenloz y Carlo.; Nin/'ck Patented July 7, 1931 CARLOS B. h'IBICX, 0I' WASHINGTON, DISTRICT 0F COLUMBIA BESONANT ELECTRICAL RELAY Application led September I, 1923. Serial En. 686,587. Y

(GRANTED mln THE ACT l' mCH 3, 1883, AS AKENDED APRIL 80, 1928; 370 0. G. 757) My invention relates broadly to signaling, and more particularly to a resonant relay for operation in signaling circuits.

One of the objects of my invention is to provide a resonant relay of simplified design which is of rugged construction and yet electrically sensitive and highly selective for signals of a particular frequency.

Another object of the invention is to prom vide a resonant relay having a pair of resonant members mechanically coupled together in such manner that the position of one of the members may be adjustably chosen with respect to the other member to `give for a selected frequency of the relay a desired amplitude of vibration of one of said members with a minimum of coupling between the members.

Another object of the invention is to provide a resonant relay construction with means for measuring quantitatively the energy sup plied to the electromagnetic system.

Other and further objects of my invention will be understood from the specification hereinafter following by reference to the accompanying drawings, in which:

Figure 1 is a plan view of the resonant relay construction of my invention; 2 1s al view partially in cross-section showing the relationship of the resonant members which I provide in my relay; Fig. 3 is a side view of my relay showing the arrangement of the device as a measuring instrument; Fig. 4 is a plan view of the operating magnets of the relay with the resonant members and'supports therefor removed; and Fig. 5 illustrates a method of mechanically coupling the resonant members of my relay to each other.

Referring to the drawings in detail, reference character 1 represents a4 steel blade or reed firmly secured at its base 2 to a supporting rin member 3. The free end of the reed 1 exten s over and close to the poles 4-4 of an electromagnet 5. The dimensions of this 15 reed are chosen so that it tends to vibrate with a period corresponding to the frequency of the electrical impulse for which the relay is designed. This impulse is applied to the windings of the magnets 5. I prefer to use a two pole magnet as indicated in the drawings, but it will be understood that a single magnet or other suitable arrangement may be used. On this reed 1 is mounted a contact wire or other resonant member 6 which pro- )ect-s in a direction substantially normal to the axis of the reed 1 and is so roportioned that the wire or ton ue 6 ten s to vibrate about its base point g with a period of its own but the same as that of the reed 1. l prefer to make the vibrator 6 of a nickel plated steel wire, though other materials may be used, particularly nickel or platinum.

Then bent end 9 of vibrator 6 wnen set in motion with sufficient amplitude, comes in Contact with contact block livwhich is usum ally provided with a mercury surfaced contact 11. If the vibration is great enough, vibrator 6 hits Contact 11 with sutlicient force to cause a recoil which produces harmful irregularities in the action of the relay and possibly injury to the vibrator. To control this, a stop screw 12 mounted on support 14 is provided so that when vibration ot reed 1 has reached a certain predetermined amplitude it comes up against stop screw 12 and no greater amplitude can -be obtained, no matter how strong the impulse acting on 1. This provides a means of limiting the amplitude of vibration of 1 and, therefore, 6, to a fixed maximum Value, so that a single setting of contact opening may produce the best results over a wide range of vibrator input energy. The support 14 is mounted on the ring mem- `ber 3 by means of screws l5.

The before described system has two mechanically coupled vibrating members 1 and 6 of like natural frequency. Such a system has two resonant frequencies, one above and one below the'value of the like 'resonance frequencies of the non-coupled members. These 'W two frequencies lie the nearer together the looser the coupling, and, if the coupling be very loose, practically merge in each other to orm a single resonance peak like that of the individual members. Due to the damp- 96 Aing always present in such systems the resonant peaks fall off gradually on both sides so that, when there are two resonant peaks, a range or band of frequencies of practically uniform amplitudes is formed between them um through carrier 2Q.

with the result of a material decrease in the sharpness of'-- selectivity of the system. In the case of a very loose coupling with only one resonance peak the selective response wlll be much more sharply delined.

I obtain a very loose coupling between the two members by utilizing only the smaller amplitude of the reed 1 for transferring vibromotive forces to the tongue 6. All points of thereed swing on arcs about the attaching point of the reed. This arcuate motion can be resolved into two components at rlght angles to each other representing the cosine and sine of the arc, the former lying in the axis of the reed or parallel to the pole faces of the magnet and the latter being perpendicular to that axis. Since the vibrations sweep over only small arcs, the cosine or axial component is appreciably smaller than the normal component, As is evident from Fig. 2 only this smaller component will vibromotively affect the tongue.

The tongue may have any position in the previously defined sense along the length of the reed. For a given signal frequency this position is determined by the following considerations. With a given inertia and stiffness of the tongue the amount of energy to be transferred from the reed to the tongue is determined by the desired amplitude of the tongue and the damping at this amplitude. The amplitude should at least be sufficient to insure perfect contact with contact block4 10. On the other hand, the amplitude should not exceed materially this threshold value in order to avoid excessive damping or energy dissipation. For this reason, I provide a wide axial adjustability of the position of the tongue on the reed between a maximum and practical zero value. It will be seen, now, that I have established between the two members a very loose coupling of such nature that, for different operating frequencies of the device, a disposition of the parts may be chosen which insures a desired amplitude of the tongue at minimum coupling or maximum selectivity of the system.

The member 3 is supported with relation t0 the magnet casing 16 by means of threaded ring 17 having right angled exterior walls at 18 forming a support for the substantially ring shaped member 19 which is attached over the ring 17 by means of thumb screws 19a. The member 19 carries an extension 20 at one side thereof forming a support for standard 21 on which is mounted a carrier 22 adjustable to any position on the standard 21 by means of thumb screw 23 within the limits of the plane of the extended support Q0 and the end oi the standard Q1 at 2a.

The opening of the contact between 9 and 11 is controlled by a screw lecd 25 passing The head of this screw may be fitted with a dial Q6 laid ott in dcgrees, or in some other contcnicnt scale, so

that a micrometer adjustment is formed, permitting the measurement of contact opening in terms of rotation of this dial with reference to pointer 27. As the amplitude of vibration of 6 is a. function of the electrical energy applied. to magnets 5-5 this feature provides a means of measuring quantitatively the energy supplied to the magnets. Thus the relay may become a means of measuring electrical impulses like received radio signals which are too small to be measured conveniently with ordinary electrical instruments. To thus employ the relay it is necessary to withdraw the stop screw 1&2 to a point where it. does not interfere with the vibration of reed 1.

The electrical energy supply at 5 5 may have an alternating electromotive force of pure sine wave form which is most desirable. Frequently it will be distorted by harmonics and this distortion may be increased by the counter E. M .Ff due to the reaction of the vibrating reed 1 on the magnetic field. The effect of these harmonics can be reduced by placing a condenser in parallel with the terminals of the electromagnets 5 chosen of a size to electrically tune the system to the fundamental frequency of the incoming impulses. This increases the sensitivity, selectivity and stability of the device.

In assembling my relay construction I determine the mechanical coupling between the resonant members 1 and 6 which gives maximum etliciency for the particular working frequency. The vibrator member 6 is then soldered in copper rivet 28 at 7 and the reed 1 apertured as represented at 29 to enable the rivet to be passed through theA reed. The edges of the rivet are then flattended to securely couple the member l with the member 6 at the selected position.

I employ my relay construction in various electrical circuits and particular circuits functioning in signaling systems to control other circuits on the receipt of signals of predetermined characteristics. It will be understood that while I have described my invention in a certain particular embodiment that various modifications may be made within the scope of the appended claims without departing from the spirit of my invention.

The invention herein described may be manufactured and used by or for the Government of the United States for governmental purposes without the payment to me of any royalty thereon or therefor.

Having thus described my invention, what I claim and desire to secure by Letters Patent of the United States is as follows:

l. A resonant relay including in combination an electromagnetic means adapted to be supplied with periodic electrical currents, a. reed having two components of vibration and resonant to said periodic currents adapted to be vibrated by said electromagnetic means, a vibrator mounted upon said reed and substantially normal to one of said components of vibration thereof and resonant thereto, a contact member carried at the extremity of said vibrator, and an adjustable Contact adjacent the contact on said vibrator.

2. A relay including in combination an electroma net, an elongated vibratory reed operated y said magnet, said reed being mounted so as to have different amplitudes of vibration throughout its length at least two components of vibration, and a second vibratory elementhaving the same natural period as said tirst vibratory element and mounted thereon substantially normal to one component of vibration of said reed so as to be excited by an amplitude of vibration of said first element less than maximum.

3. A vibratory system.v including an elongated vibratory reed of pre-determined period, means securing said element for vary.- ing amplitude of vibration throughout its length, and a plurality of components of vibration,` and a second vibratory element having the same natural period as said first element and mounted thereon at a point of vibration of amplitude less than maximum and substantially normalto one component of' vibration of said reed.

4. A vibratory system including a vibratorily mounted reed having a plurality of components of vibration and a vibratory member having the same natural period as said tongue mounted thereon and substantially normal to one component of vibration of said reed.

nents of vibration, means for actuating said element at its natural period of vibration, and a driven element of the same natural period as said driving element directly and loosely coupled thereto whereby said driven element is actuated by the lesser componentl of vibration of said driving element.

7. A vibratory system including a drivin element having a plurality of components 0 vibration and a directly connected element driven by one of the lesser components of vibratol'y reed, means for vibrating said reed whereby points along said reed have two components of motion, the smaller of which is substantially parallel to the position of rest of said reed, stationary and moving contacts, and means mechanically coupling said reed and said movable contact, whereby said movable contact is actuated by said lesser component of movement of said reed and at an amplitude greater than said lesser component of movement of said reed.

9. In an electric translating device, a vibratory reed, means for vibrating said reed whereby points along said reed have` two components of motion, the lesser of which is substantially parallel to the position of rest of said reed, stationary `and moving contacts, and means mechanically coupling said reed and said movable contact, said mechanical coupling means having substantially the same resonant frequency as said reed, whereby said movable contact is actuated by said lesser component 'of movement of said reed and at an amplitude greater than saidlesser component of said reed.

10. In an electric translating device, a vibratory member, means for imparting to CARLOS B. MIRICK.

bration of said driving element, said elements having the same natural periods of vibration, and means associated with said system for measuring the amplitude of vibration of said.

driven element.

v8. In an electric, translating device, a vi-' vthis member angular vibrations characte'r--"v losl 

